GI: Anorectal disorders Flashcards
What is pruritis ani?
Itch that occurs around the anus
What can cause pruritis ani?
- Moist/solied anus
- Fissures
- Incontinence
- Poor hygeine
- Tight pants
- Threadworm
- Fistula
- Dermatoses
- Lichen sclerosis
- Anxiety
- Contact dermatitis
How would you treat someone with pruritis ani?
- Avoid scratching
- Improve perianal hygeine
- Avoid foods which loosen stool
- Soothing ointment
- Topical steroids (max 2 weeks)
- Oral antihistamine
What are anal fissures?
Painful tears in the squamous lining of the lower anal canal. Often, if chronic, they will have a sentinal pile or mucosal tag at the external aspect
What sex do anal fissures occur more commonly in?
Males
What are causes/predisposing features of anal fissures?
- Hard stools - most common
- IBD esp crohns
- Constipation
- Syphillis
- Herpes
- Trauma
- Anal cancer
- Psoriasis
Rsk factors of anal fissure
Constipation
Dehydration
Inflammatory bowel disease
Chronic diarrhoea
Prsesentation of anal fissure
90% in posterior midline (anterior more common following birth)
- PAINFUL bleeding post defication
- “like passing broken glass
Why do anal fissures take a significant amount of time to heal?
Spasm around the area leads to relative ischaemia, meaning that fissures take longer to heal
What might you consider doing in someone with anal fissures if you suspected a sinister cause?
Proctoscopy/Sigmoidoscopy
How would you manage someone with anal fissures?
- Dietary fibre
- Fluids
- Stool softener
- Hygeine advice
-
Consider medical
- Topical 5% lidocaine + 0.2% GTN Paste (
- Topical 2% Diltiazem
What medical treatment can be used to treat anal fissures?
- Topical 5% lidocaine + 0.2% GTN Paste
- GTN ointment relaxes internal sphincter by increasing blood supply
- Topical 2% Diltiazem
- A CCB relaxes internal sphincter by preventing spasm
- Botulinium toxin
- Relaxes internal sphincter, lasts for 2 months.
What would you consider dioing in a patient with anal fissures where conservative and medical management has failed?
Sirgical management
Lateral partial internal sphinterectomy
Indicated if conservtive measures fail or chronic fissure - incontinence
What is a anorectal abscess?
Abscess which is usually caused by gut bacteria, which can occur in the perianal, ischiorectal, intersphincteric or supralevator regions
Predisposing factors to ano-rectal abscess
CD
DM
Malignancy
Immunosupression
What is thought to cause ano-rectal abscess
Thought to b plugging of anal ducts (which drain anal glands). Blockage of these ducts cause stasis of bacteria
Presentation anorectal abscess
Pain +/- localised severe itching/discharge
Wrose on sitting down
Systemic features in severe eg feature
Typical bacteria anorectal abscess
E. Coli
Enterococcus
Bacteriods
How would you manage a perianal abscess?
Incise and drain under GA
Antibiotics
What diseases are perianal abscesses associated with?
- Diabetes mellitus
- Crohn’s
- Malignancy
- Fistulae
What is a fistula in ano?
A track communicating between the skin and anal canal/rectum. Often occurs following the development of an abscess
How do fistulae in ano form?
Blockage of deep intramuscular gland ducts thought to predispose to the formation of abscesses, which discharge to form fistulas
What are causes of fistula-in-ano?
- Perianal disease (majority)
- Abscesses
- Crohn’s Disease
- TB
- Diverticular disease
- Rectal carcinoma
- Immunocompromise
What is goodall’s rule?
Predicts trajectory of fistula depending on location
If anterior it tracts in a straight line
If posterior the internal opening is at the 6 oclock position ( curved)
Presentation of anal fistula
Pain - throbbing and constant
Perianal dishcarge (blood and pus) - as a result of associated infection
What is the following type of fistula-in-ano?
Transphincteric fistula
What is the following type of fistula-in-ano?
Intersphincteric fistula
What type of fistula-in-ano is the following?
Extrasphincteric fistula
What type of fistula-in-ano is the following?
Suprasphincteric fistula
How would you investigate a fistula in ano?
- MRI
- Endoanal US scan
Rigid sigmoidoscopy, fistulography
How would you manage someone with fistula-in-ano?
-
Fistulotomy + excision
- High (transphincteric)- seton suturing tightened over time to maintain continence
- Low (superficial) - heal by secondary intention
Complications of anal fistula
Peri-anal abscess
Recurrence
Faecal incontienance post op
What are causes of anal ulceration?
- Crohn’s
- Anal cancer
- Lymphogranuloma venerum
- TB
- Syphillis
What is a pilonidal sinus?
Obstruction of the natal cleft hair follicles approximately 6 cm above the anus.
In growing hair excites a foreign body reaction and may cause secondary tracks to open laterally, with abscesses extruding foul, smelly discharge
So hows a pilonidal sinus different to an abscess?
PS open up onto skin but does not continue into anal canal like a fistula.
Distinction formally done by rigid sigmoidoscopy
What sex does pilonidal sinuses occur most commonly in?
Males
Managment of pilonidal sinus
Offer hygeine adivce and hair removal adice
Incision and drainage of abscess/sinus (acute)
Recurrence may require wide exciion and ksin flap
What percentage fo those with rectal prolapse are incontinent?
75%
Why does rectal prolapse occur?
Lax sphincter, combined with prolonged straining. It is also related to chronic neurological and psycholoigical disorders.
There are two types:
type 1 is the mucosa (partial - loosening and stretching of connective tissue)
type 2 is all layers (defect of fascia in pelvic region eg constipation, chronic cough, multiple vaginal delviery)
Presentation of rectal prolapse
Incontinence
Perianal symptoms - rectal bleeding
Reduced sphinter tone on DRE
How would you manage someone with rectal prolapse?
- Abdominal approach - fix rectum to sacrum (rectoplexy) +/- mesh insertion +/- rectosigmoidectomy (Altmeire’s procedure)
- Perineal approach - Delorme’s procedure - resect close to dentate line and suture mucosal bouncaries
-
For those unfit for surgery -
- Improve fibre intake
- Decrease constipation with lactulose
What are risk factors for the development of anal cancer?
- Anoreceptive intercourse
- HPV
- HIV
- Increased age, smoking, crohns
Where do anal tumours above the dentate line spread to?
Pelvic lymph nodes
Where do anal cancers spread to if they are below the dentate line?
Inguinal lymph nodes
Note 80% are squamous
How do those with anal cancer tend to present?
- Bleeding
- Pain
- Bowel habit change
- Pruritis ani
- Masses
- Stricture
Investigations anal cancer
Protoscopy and biopsy
Consider HIV testin
USS guided and fine needle biopsy of any plapable lymph nodes
CT mets, MRI degree of spread
How would you manage someone with anal cancer?
- Chemoradiotherapy - radio + flourouracil + mitomycin/cisplatin (external beam)
-
Consider surgery
- Abdominoperineal excision
- For large lesions - AP resection and colostomy
What are haemorrhoids?
Disrupted and dilated anal cushions. The anus is lined mainly by discontinuous masses of spongy vascular tissue - anal cushions - which contribute to anal closure. These are prone to disruption and displacement, and can protrude forming piles
Trauma to these piles can lead to leaking of the capillaries of underlying lamina propria
“Abnormal swelling/enlargement of anal vasculature cushions”
PILES ARE NOT VARICOSE VEINS
Why are haemorrhoids above the dentate line not normally painful
No sensory fibres above the dentate line - not painful unless they thrombose and are gripped by anal sphincter
What are causes of haemorrhoids?
- Constipation with prolonged staining - main cause
- Congestion - pelvic tumour
-
Intra-abdominal pressure
- Pregnancy
- Chronic cough
- Ascietes
- Obesity
- Cardiac failure
- Portal hypertension
What is the pathogenesis of haemorrhoids?
Vascular cushion protrudes through the tight anus, becomes more congested, and hypertrophy to protrude again more readily. These protrusions may then strangulate.
- Displacement and dilatation of one or more anal cushions - normally act to asist anal sphincter in maintaining continence
- BVs become inflammed and swollen
- Tight anus, more congested so hypetrophying to protrude organ more readily
What are symptoms of haemorrhoids?
- Painless bright red rectal bleeding - often coating stools/on tissue/dripping into toilet
- Mucous
- Pruritis ani
- Pain on defication
- Severe anaemia can occur
- May be soiling due to impaired continence/mucous discharge
A thrombosed haemorrhoid will present as a purple/blue oedematous, tense and tender perianal mass
What features might suggest a more sinister cause of what you initially think are haemorrhoids?
- Weight loss
- Tenesmus
- Change in bowel habit
Whaat are important aspects of the examination that you need to consider when examining someone with suspected haemorroids?
- Abdo exam - look for sinister pathology
- PR exam - prolapsing piles, other pathology
- Protoscopy - visualise haemorrhoids
- Colonoscopy/flexible sigmoidoscopy if proximal pathology suspected - exclude higher pathology eg malignancy
What is classed as a first degree haemorrhoid?
Remains in the rectum
What is classed as a 2nd degree haemorrhoid?
Prolapse through the anus on defecation but spontaneously reduce
What is classed as a 3rd degree haemorrhoid?
Prolapse on defecation but require digital reduction
What is classed as a 4th degree haemorrhoid?
Remain persistently prolapsed
Where do internal haemorrhoids originate from?
Above the dentate line
Where do external haemorrhoids originate from?
Below dentate line
Where do mixed haemorrhoids originate from?
Both above and below dentate line
How would you manage haemorrhoids?
Conservative/Medical - 1st degree
- High fibre diet + fluids
- Topical analgesia
- Stool softeners
95% managed conservatively esp if asymptomatic
Interventional - 2nd and 3rd degree
- Sclerotherapy
- Band ligation - haemorrhoid drain into end of a suction gun and a rubber band palced at end, after 10 days
- Infrared coagulation - in out patient
- Bipolar diathermy
- Cryotherapy
Surgical
- Excisional Haemorrhoidectomy
- Stapled haemorrhoidopexy
Complications of haemorrhoids
Strangulation - blood supply to prolapsed haemorrhoid is restricted due to contraction of anal sphincter, resulting in pain and swelling
May become thrombosed, leading to ulceration which is extremely painful.
Skin tags
Perianal sepsis
What’s a perianael haematoma?
Rupture of perianal subcutaneous blood vessle
Presentation of perianal haematoma
Perianal pain
Blue/black bulge at anal markin (dark blueberry under skin)
Managemetn perianal haematoma
Tends to resolve spontaneously
Medical: incision - indicated only for pain releif
